RE: Once again: OSPF demand circuit & ISDN

From: Michael Snyder (msnyder@xxxxxxx)
Date: Sun Jun 30 2002 - 17:48:48 GMT-3


   
Boy, you pinned that one down well.

I've noticed that when I mixed legacy and profiles together with
multilink, that sometimes I get a second channel coming up on the return
ping.

For example if router C pings router D, the ping leaves on bri0:1 but
comes back on bri0:2 !

Didn't have time to trouble shoot it, other that checking the dial
strings and dialer maps. Everything looks correct, but the second
router is setting up a return call for no reason I can figure out.

I don't know if this is just a simple mistake on my part, or if such
behavior is also related to your problem.

Router C

!
interface BRI0
 no ip address
 encapsulation ppp
 dialer pool-member 10
 isdn switch-type basic-net3
 isdn spid1 1111
 isdn spid2 1112
 ppp multilink
!
interface Dialer10
 ip address 172.168.65.2 255.255.255.0
 encapsulation ppp
 ip ospf cost 10000
 ip ospf demand-circuit
 dialer pool 10
 dialer idle-timeout 45
 dialer string 2221
 dialer string 2222
 dialer load-threshold 3 outbound
 dialer-group 10
 ipx network 65
 ppp authentication pap
 ppp pap sent-username router1 password 7 13151601185D
 ppp multilink

Router D
!
interface BRI0
 ip address 172.168.65.1 255.255.255.0
 encapsulation ppp
 ip ospf cost 10000
 dialer idle-timeout 45
 dialer map ip 172.168.65.2 broadcast 1111
 dialer map ip 172.168.65.2 broadcast 1112
 dialer map ipx 65.0000.0000.0003 broadcast 1111
 dialer map ipx 65.0000.0000.0003 broadcast 1112
 dialer load-threshold 3 outbound
 dialer-group 10
 ipx network 65
 isdn switch-type basic-net3
 isdn spid1 2221
 isdn spid2 2222
 ppp authentication pap
 ppp pap sent-username router2 password 7 105E080A1645
 ppp multilink

C#p 172.168.65.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.168.65.1, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 36/36/36 ms
C#show us
    Line User Host(s) Idle Location
   0 con 0 idle 07:52:08
   2 vty 0 dd 00:24:11 ff
* 3 vty 1 idle 00:00:00 aa

  Interface User Mode Idle Peer
Address
  BR0:1 router2 Sync PPP - Bundle: Di10
  BR0:2 router2 Sync PPP - Bundle: Di10

C#show isdn a
------------------------------------------------------------------------
--------
                                ISDN ACTIVE CALLS
------------------------------------------------------------------------
--------
Call Calling Called Remote Seconds Seconds Seconds
Charges
Type Number Number Name Used Left Idle
Units/Currency
------------------------------------------------------------------------
--------
Out 2221 D 15 - - 0
In 2222 1112 D 10 - -
------------------------------------------------------------------------
--------

If anyone sees my mistake, please email me. BTW, I know the
load-threshold 3 is a bit low, but I've used it before and it didn't
bring up both channels in the other configs I've done.

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Carlos G Mendioroz
Sent: Sunday, June 30, 2002 2:45 PM
To: Groupstudy ccielab list
Subject: Once again: OSPF demand circuit & ISDN

Hi,
got into a troublesome area, and no luck in getting out.

I have a simple setup, 2 routers linked via serial and ISDN.
OSPF in both links, ip ospf demand-circuit on ISDN, only
one side dialing. No other routing protocol involved.

It seems to break if I set dialer-profiles + multilink ppp
at the receiving side. Dialer profile w/o MPPP is ok.
Interface config (aka legacy) with or w/o MPPP is ok.
But as soon as I set dialer + multilink, there seems to
be a link down transient at the receiving side,
that gets translated in a LSA update that in turn triggers
a new call just after the previous one is torn down
(LS sequence jumps up by 2 each time).

I've read some 100+ posts on the subject but nothing that
clears this (but, maybe, some suggestions to filter
ospf traffic as interesting, that is not what I want to do).

Have tried 12.1.13, 12.1.15, 12.2.8T4 and all do the same.

Here's the receiving side conf:

interface BRI0/0
 no ip address
 encapsulation ppp
 dialer pool-member 1
 isdn switch-type basic-ni
 isdn spid1 1555000021
 isdn spid2 1555000021
 ppp authentication chap
 ppp multilink

interface Dialer1
 ip address 172.16.200.1 255.255.255.0
 encapsulation ppp
 ip ospf demand-circuit
 dialer pool 1
 dialer remote-name 2602
 dialer-group 1
 ppp authentication chap
 ppp multilink

Any suggestion as to how to get this working (or definitive
reason as to why it will not) is very welcome!

--
Carlos G Mendioroz  <tron@huapi.ba.ar>  LW7 EQI  Argentina


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